/*
*
* Copyright (c) 2006-2011 Sam Collett (http://www.texotela.co.uk)
* Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
* and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
*
* Version 1.3.1
* Demo: http://www.texotela.co.uk/code/jquery/numeric/
*
*/
(function($) {
/*
* Allows only valid characters to be entered into input boxes.
* Note: fixes value when pasting via Ctrl+V, but not when using the mouse to paste
* side-effect: Ctrl+A does not work, though you can still use the mouse to select (or double-click to select all)
*
* @name numeric
* @param config { decimal : "." , negative : true }
* @param callback A function that runs if the number is not valid (fires onblur)
* @author Sam Collett (http://www.texotela.co.uk)
* @example $(".numeric").numeric();
* @example $(".numeric").numeric(","); // use , as separator
* @example $(".numeric").numeric({ decimal : "," }); // use , as separator
* @example $(".numeric").numeric({ negative : false }); // do not allow negative values
* @example $(".numeric").numeric(null, callback); // use default values, pass on the 'callback' function
*
*/
$.fn.numeric = function(config, callback)
{
if(typeof config === 'boolean')
{
config = { decimal: config };
}
config = config || {};
// if config.negative undefined, set to true (default is to allow negative numbers)
if(typeof config.negative == "undefined") { config.negative = true; }
// set decimal point
var decimal = (config.decimal === false) ? "" : config.decimal || ".";
// allow negatives
var negative = (config.negative === true) ? true : false;
// callback function
callback = (typeof(callback) == "function" ? callback : function() {});
// set data and methods
return this.data("numeric.decimal", decimal).data("numeric.negative", negative).data("numeric.callback", callback).keypress($.fn.numeric.keypress).keyup($.fn.numeric.keyup).blur($.fn.numeric.blur);
};

$.fn.numeric.keypress = function(e)
{
// get decimal character and determine if negatives are allowed
var decimal = $.data(this, "numeric.decimal");
var negative = $.data(this, "numeric.negative");
// get the key that was pressed
var key = e.charCode ? e.charCode : e.keyCode ? e.keyCode : 0;
// allow enter/return key (only when in an input box)
if(key == 13 && this.nodeName.toLowerCase() == "input")
{
return true;
}
else if(key == 13)
{
return false;
}
var allow = false;
// allow Ctrl+A
if((e.ctrlKey && key == 97 /* firefox */) || (e.ctrlKey && key == 65) /* opera */) { return true; }
// allow Ctrl+X (cut)
if((e.ctrlKey && key == 120 /* firefox */) || (e.ctrlKey && key == 88) /* opera */) { return true; }
// allow Ctrl+C (copy)
if((e.ctrlKey && key == 99 /* firefox */) || (e.ctrlKey && key == 67) /* opera */) { return true; }
// allow Ctrl+Z (undo)
if((e.ctrlKey && key == 122 /* firefox */) || (e.ctrlKey && key == 90) /* opera */) { return true; }
// allow or deny Ctrl+V (paste), Shift+Ins
if((e.ctrlKey && key == 118 /* firefox */) || (e.ctrlKey && key == 86) /* opera */ ||
(e.shiftKey && key == 45)) { return true; }
// if a number was not pressed
if(key < 48 || key > 57)
{
var value = $(this).val();
/* '-' only allowed at start and if negative numbers allowed */
if(value.indexOf("-") !== 0 && negative && key == 45 && (value.length === 0 || parseInt($.fn.getSelectionStart(this), 10) === 0)) { return true; }
/* only one decimal separator allowed */
if(decimal && key == decimal.charCodeAt(0) && value.indexOf(decimal) != -1)
{
allow = false;
}
// check for other keys that have special purposes
if(
key != 8 /* backspace */ &&
key != 9 /* tab */ &&
key != 13 /* enter */ &&
key != 35 /* end */ &&
key != 36 /* home */ &&
key != 37 /* left */ &&
key != 39 /* right */ &&
key != 46 /* del */
)
{
allow = false;
}
else
{
// for detecting special keys (listed above)
// IE does not support 'charCode' and ignores them in keypress anyway
if(typeof e.charCode != "undefined")
{
// special keys have 'keyCode' and 'which' the same (e.g. backspace)
if(e.keyCode == e.which && e.which !== 0)
{
allow = true;
// . and delete share the same code, don't allow . (will be set to true later if it is the decimal point)
if(e.which == 46) { allow = false; }
}
// or keyCode != 0 and 'charCode'/'which' = 0
else if(e.keyCode !== 0 && e.charCode === 0 && e.which === 0)
{
allow = true;
}
}
}
// if key pressed is the decimal and it is not already in the field
if(decimal && key == decimal.charCodeAt(0))
{
if(value.indexOf(decimal) == -1)
{
allow = true;
}
else
{
allow = false;
}
}
}
else
{
allow = true;
}
return allow;
};

$.fn.numeric.keyup = function(e)
{
var val = $(this).value;
if(val && val.length > 0)
{
// get carat (cursor) position
var carat = $.fn.getSelectionStart(this);
// get decimal character and determine if negatives are allowed
var decimal = $.data(this, "numeric.decimal");
var negative = $.data(this, "numeric.negative");

// prepend a 0 if necessary
if(decimal !== "" && decimal !== null)
{
// find decimal point
var dot = val.indexOf(decimal);
// if dot at start, add 0 before
if(dot === 0)
{
this.value = "0" + val;
}
// if dot at position 1, check if there is a - symbol before it
if(dot == 1 && val.charAt(0) == "-")
{
this.value = "-0" + val.substring(1);
}
val = this.value;
}

// if pasted in, only allow the following characters
var validChars = [0,1,2,3,4,5,6,7,8,9,'-',decimal];
// get length of the value (to loop through)
var length = val.length;
// loop backwards (to prevent going out of bounds)
for(var i = length - 1; i >= 0; i--)
{
var ch = val.charAt(i);
// remove '-' if it is in the wrong place
if(i !== 0 && ch == "-")
{
val = val.substring(0, i) + val.substring(i + 1);
}
// remove character if it is at the start, a '-' and negatives aren't allowed
else if(i === 0 && !negative && ch == "-")
{
val = val.substring(1);
}
var validChar = false;
// loop through validChars
for(var j = 0; j < validChars.length; j++)
{
// if it is valid, break out the loop
if(ch == validChars[j])
{
validChar = true;
break;
}
}
// if not a valid character, or a space, remove
if(!validChar || ch == " ")
{
val = val.substring(0, i) + val.substring(i + 1);
}
}
// remove extra decimal characters
var firstDecimal = val.indexOf(decimal);
if(firstDecimal > 0)
{
for(var k = length - 1; k > firstDecimal; k--)
{
var chch = val.charAt(k);
// remove decimal character
if(chch == decimal)
{
val = val.substring(0, k) + val.substring(k + 1);
}
}
}
// set the value and prevent the cursor moving to the end
this.value = val;
$.fn.setSelection(this, carat);
}
};

$.fn.numeric.blur = function()
{
var decimal = $.data(this, "numeric.decimal");
var callback = $.data(this, "numeric.callback");
var val = this.value;
if(val !== "")
{
var re = new RegExp("^\\d+$|^\\d*" + decimal + "\\d+$");
if(!re.exec(val))
{
callback.apply(this);
}
}
};

$.fn.removeNumeric = function()
{
return this.data("numeric.decimal", null).data("numeric.negative", null).data("numeric.callback", null).unbind("keypress", $.fn.numeric.keypress).unbind("blur", $.fn.numeric.blur);
};

// Based on code from http://javascript.nwbox.com/cursor_position/ (Diego Perini <dperini@nwbox.com>)
$.fn.getSelectionStart = function(o)
{
if (o.createTextRange)
{
var r = document.selection.createRange().duplicate();
r.moveEnd('character', o.value.length);
if (r.text === '') { return o.value.length; }
return o.value.lastIndexOf(r.text);
} else { return o.selectionStart; }
};

// set the selection, o is the object (input), p is the position ([start, end] or just start)
$.fn.setSelection = function(o, p)
{
// if p is number, start and end are the same
if(typeof p == "number") { p = [p, p]; }
// only set if p is an array of length 2
if(p && p.constructor == Array && p.length == 2)
{
if (o.createTextRange)
{
var r = o.createTextRange();
r.collapse(true);
r.moveStart('character', p[0]);
r.moveEnd('character', p[1]);
r.select();
}
else if(o.setSelectionRange)
{
o.focus();
o.setSelectionRange(p[0], p[1]);
}
}
};

})(jQuery);
